A. Field of Invention
The present invention relates to wireless systems, and more particularly, to a system and method for predicting wireless network traffic.
B. Description of Related Art
Wireless systems, such as cellular wireless systems or personal communication systems (PCS), are growing due to an increase of mobile subscribers. Worldwide public demand, availability of cost-effective technology, and recent regulatory actions have all contributed to this growth of wireless telecommunications. With an increase in telecommunications traffic, infrastructures of cellular wireless systems may need to be reconfigured.
The infrastructure of a cellular wireless system may be reconfigured in many ways, such as by reallocating resources, reconfiguring cell sites, or by adding wireless communication equipment, such as a base transceiver station (BTS), a base station controller (BSC), or additional antennas for a BTS. Many factors must be considered for allocating wireless communication equipment, such as availability of base station sites, available telecommunication traffic capacity at each base station, and wireless service quality at various high telecommunication traffic areas.
Each cell site of a wireless system has a BTS, which typically consists of a tower, antennas, and a small building containing radio equipment. The antennas provide a radiation pattern that defines a coverage area, which has sectors that define regions of wireless signal coverage. The coverage area of a BTS may be reconfigured as well to provide service to additional areas. In addition, an increase in cell sites may be necessary to support an increase in wireless telecommunication traffic. New cell sites may be necessary in rural areas, whereas existing wireless cell sites may require cell site splitting in urban areas.
Cell sites can be allocated in a manner such that a large percentage of mobile station subscribers can obtain a sufficient signal strength to achieve an acceptable quality of service (QoS). QoS can be affected by many factors including transmission path obstruction, cell site overlap (e.g., 15 percent is normal), and system redundancy. The maximum distance that a mobile station can be located from a cell site while still achieving acceptable service reliability should also be considered. Several network parameters may be analyzed to determine such a distance including carrier-to-noise ratios (CNRs), self-repeat site interference, and/or fade margins.
In planning a wireless system, call models and subscriber forecasts may dictate expected growth of telecommunication usage. Wireless system planning tools available today focus primarily on optimizing a present wireless system, or locating optimal positions for a new cell site. Such tools cannot predict future capacity problems and/or estimate future telecommunication traffic on a wireless system.
Typically, design and implementation of a new cell site requires a substantial period of time. Implementation requires selecting a suitable location for the cell site, obtaining city permits and approvals, constructing the cell site, creating backhaul circuits for the cell site, and testing the cell site. A capacity problem may arise prior to completion of the new cell site. Therefore, planning for future capacity problems in a wireless network may be desirable in order to implement new cell sites before a capacity problem occurs.